The spinal column is a bio-mechanical structure principally composed of vertebrae and intervertebral disks, along with ligaments, muscles, collectively whose primary functions may be regarded as including support of the body as well as protection of the spinal cord and associated nerve roots. The spinal column's body support functionality involves distribution of weight from the various extremities and the torso to the pelvis and legs. As individuals age, various adverse spinal column conditions may develop that often result in back pain. Non-limiting examples of such conditions include spinal stenosis, thickening of spinal column constituent bones, facet antropathy, facet joint arthritis, facet synovial cyst, annular tear, painful disc disruption, and segmental instability.
Currently, pain originating from such conditions (and others) may be treated with medications and/or surgically. However, it is often the case that at present, in severe circumstances, such treatment requires invasive surgical correction. A principle goal for any such surgical correction should be to minimize or eliminate the need for major surgery in all patients and, most especially, for elderly patients.
Accordingly, to address such defective spinal column conditions and others, there is need to develop devices and methodologies that are minimally invasive and that can be well tolerated by all patients, especially elderly patients.
Prior efforts to address such spinal column conditions have resulted in the development of some forms of interspinous implants for implantation between adjacent spinous processes for the relief of pain associated with the spine. One such device is described in U.S. Pat. No. 6,695,842 to Zucherman et al., entitled “Interspinous Process Distraction System and Method With Positionable Wing and Method” with an issue date of Feb. 24, 2004. Such Zucherman et al. device includes a central spacer and a pair of end wings in a complex configuration including a fastener with a tapered head. The tapered head cooperates with a similarly tapered cavity portion of one of the wings to provide adjustment of the one wing relative to the other wing.
A similar device is described in U.S. Patent Application Publication U.S. 2004/0181282 A1 to Zucherman et al., entitled “Interspinous Process Apparatus and Method With A Selectably Expandable Spacer” with a publication date of Sep. 16, 2004. The device disclosed in such '282 publication is similar to that of the previously mentioned '842 patent but provides a selectably expandable spacer that, by adjusting a screw mechanism, can be adjusted in place. The Zucherman et al. '282 published patent application, like the '842 patent, suffers the same inherent complexity issues. In addition, from a surgery management perspective, the potential need to access such adjusting screw mechanism has the potential for requiring additional invasive procedures on the patient.
While various implementations of implantable interspinous internal fixation/distraction devices have been developed, no design has emerged that generally encompasses all of the desired characteristics as hereafter presented in accordance with the subject technology.